Product applicators are designed to deliver a quantity of product. In consumer goods there are, broadly, two types of applicators. There are applicators that are separable from a product container/reservoir. Throughout the specification, a “separable applicator” is one that is disconnected from a product reservoir at the time of applying product to a target surface. In use, a separable applicator is loaded with product from a product reservoir for transfer to a target surface. In contrast, there are applicators that are integral with a product container and therefore, the applicator cannot be separated from the product container. This type of device dispenses product by causing the product to flow from a reservoir, through the interior of an applicator, and out an exit structure, for transfer to a target surface.
Either applicator type is known to be coupled with a heating element to heat a product prior to and/or during dispensing and application. Specifically, there are such devices in the personal care and cosmetics fields. The present invention is concerned with the first type of heated applicator, that which is separable from a product container.
A heated applicator that is separable from a product container has different issues than a heated applicator that is integral with a dispensing container. In the case of a heated applicator that is separated from a product container at the time of use, the electronic circuitry must be housed solely within the applicator, and not within the container, if power is to be continuously supplied to the applicator. In contrast, in the case of an applicator that is integral with a dispensing container, the electronics is not limited to being housed within the applicator. The container portion provides substantially more space for a layout of electric circuits. In fact, dispensing containers with integral applicators and heating elements may be no larger than dispensing containers with integral applicators having no heating elements. Separable applicators are different, at least in cosmetics and personal care. Here, such applicators tend to be sleek and designed for easy storage in a small purse or pocket. In the personal care field, the drive is always to make smaller, more convenient applicators of this type. Therefore, when the addition of heating components to an applicator requires making the applicator larger, this is a clear disadvantage. This disadvantage is not as often encountered when designing dispensing containers with integral applicators, because dispensing containers with integral applicators do not have to be enlarged at all or to the same degree as separable applicators. The present application is concerned with separable heated applicators. The following will make clear the shortcomings of known devices of this type.
U.S. Pat. No. 5,775,344 discloses a brush-type applicator, for example, a mascara applicator, that comprises a battery, an on/off switch, and a heat facilitating strip that extends the length of the applicator rod, on the inside of the rod. However, to be effective, this patent teaches that the product reservoir must be separately heated by additional batteries and heat facilitating strips, so that the entire contents of the reservoir is uniformly and continuously heated during use. This is a disadvantage in that not all cosmetics, not even all mascaras, can be repeatedly heated and cooled without damaging the product. Therefore, this prior art device is unsuitable for products that are altered structurally or chemically by the application of too much heat or from being too often heated. This is unlike the present invention, wherein the product remaining in the reservoir is not substantially heated or heated to a much lesser degree and remains in good condition for future use. Another disadvantage of the '344 device is the additional power that must be consumed to raise the temperature of the entire contents and volume of the reservoir. This is costly and inconvenient if batteries need to be replaced often. In acknowledging this problem, the '344 reference suggests insulating the exterior walls of the container. Although no details for doing this are disclosed, it certainly makes this applicator more complex and costly than the present invention, wherein the reservoir does not need to be insulated.
It should be noted that the '344 reference does not disclose how to construct a mascara applicator with a heat facilitating strip that extends the length of the applicator rod, on the inside of the rod. No details about the heat facilitating strip or the rod are given. From the figures, one may only assume that the heat facilitating strip is a simple resistive filament. Nothing can be known for sure about the rod. Also, it is not known from this reference if a heated applicator according to the reference, by itself, in the absence of separately heating the reservoir, would be effective. Since the reference discloses the need to heat the reservoir, it may be assumed that the heated applicator of the reference could not by itself produce any useful result. It may be that a heated applicator according to the reference was unable to generate enough heat by itself, to be effective. Again, it is difficult to tell because the reference is vague on the details of the applicator construction. Nevertheless, it is the applicant's believe that construction of a mascara applicator according to '344 is not convenient from a mass manufacturing or economic point of view.
In contrast, the present invention is a heated applicator that provides sufficient energy to effectively heat a product with which it comes in contact, the reservoir not needing to be separately heated. Separate power sources and circuitry for the reservoir are optional, but not essential. An applicator according to the present invention can be adjusted so that the contents of a product reservoir are not adversely affected by the repeated heating and cooling. Furthermore, the application of the present invention uses printed circuit technology, including flexible printed circuit technology, that makes mass manufacture of heated applicators convenient and cost effective.
Seemingly, all heated cosmetic and personal care applicators utilize conventional, flexible metallic wiring and contacts for conducting electricity from a power source to a switch, then to a heating element and possibly to one or more light indicators and temperature controls, before returning to the power source. If more than one independent circuit is required, as in the '344 patent for example, then the number of wires and electrical connections increases proportionately. There are several disadvantages to this situation. First, there is the need to fit all of these flexible, flimsy wires into a small cosmetic device. Assembling such devices may need to be done by hand because of the need to fit it all in while not damaging any of the circuitry. Also, the overall size of the dispensing device may be constrained by the need for enough space to fit all of the circuitry. This may require a larger device than is aesthetically appealing or larger than a consumer has come to expect. In markets where appearance, feel and ergonomics play a significant role in market success, this disadvantage is serious. Another disadvantage is the number and type of electrical connections that must be made in a heated applicator device having stranded wire conductors. These connections may be made by soldering or twisting conductors together. Either of these is labor intensive and cost ineffective. With repeated use and wear and tear, connections of this sort may eventually fail. The result is a useless applicator and frustrated consumer. Yet another disadvantage is the relatively unsophisticated circuitry that can be reasonably incorporated into a small, inexpensive cosmetic applicator. In contrast, a heated applicator according to the present invention does not use metal wire conductors or uses substantially fewer, does not have the space constraints associated with using wire circuitry, substantially reduces the labor required to assemble an applicator and has more reliable electrical connections and sophisticated electrical options than prior art applicators.